1. Field of the Invention
The present invention relates to a terminal fitting included in a wire harness disposed in an automobile, and a method of manufacturing a wire with a terminal having the terminal fitting.
2. Description of the Related Art
Generally, a wire harness for transmitting electric power or a control signal is disposed between electronic devices. A wire harness includes one or more wires, a terminal fitting crimped to a terminal of each wire, and a connector storing the terminal fitting. This connector is fitted to a counterpart connector, whereby an electrical connection is established. A connector used for a wire harness of this type generally includes a tubular connector housing, herein a terminal fitting is stored in a terminal storage chamber (cavity) formed on the connector housing.
A terminal fitting is formed by, for example, bending a conductive plate, and includes a wire connection part connected to a wire, and an electric contact part connected to a terminal fitting in a counterpart connector. The wire connection part has a crimp part (barrel piece) crimped to a terminal of a wire with caulking, and a saw-like serration part is formed on an inner surface of the crimp part for holding a core of a wire to ensure electrical connection. There is also proposed a terminal structure in which a water stop member is provided on an inner surface of a crimp part of a wire connection part in order to close a gap with a wire to prevent water from entering a core and a serration part (see, for example, WO 2011/122622 A1).
As illustrated in FIGS. 15, 16A, 16B, 16C, 16D, and 16E, a crimp terminal 100 described in Patent Literature 1 is a female terminal connected to a counterpart male terminal, and includes an electric contact part 101 in a rectangular cylindrical shape, a wire connection part 102 mounted at the back of the electric contact part 101 and connected to a wire W, and a coupling part 103 with a cross-section of a reversed C shape, the coupling part 103 coupling these parts. As illustrated in FIGS. 16A, 16B, and 16C, the wire connection part 102 has a barrel piece 104 with a cross-section of an almost U shape which is open to one side before it is caulked (before crimped), and a saw-like serration part 105 for holding a core W1 of the wire W is formed on an inner surface of the barrel piece 104. The barrel piece 104 also has a sheet-type holding part 106 extending backward from the serration part 105. This holding part 106 holds an insulating coating W2 of the wire W.
The barrel piece 104 of the crimp terminal 100 is also provided with a water stop member 107 formed continuously along edges of four sides on its inner surface, and a water stop member 108 formed along an edge of an opening on one outer surface. As illustrated in FIGS. 16D and 16E, in the state in which the barrel piece 104 is caulked to be crimped to the wire W, the opening edges of the barrel piece 104 are overlapped to cover the wire W, the inner water stop member 107 is in close contact with the insulating coating W2 of the wire W, and the water stop members 107 and 108 are in close contact with each other at the overlapping part. In addition, the barrel piece 104 is crushed with the coupling part 103 by caulking at the front part of the wire connection part 102, whereby the inner water stop member 107 closes the gap between edges of the barrel piece 104. Thus, the connection part between the core W1 of the wire W and the serration part 105 is waterproofed.
However, in the conventional terminal fitting described in WO 2011/122622 A1, the barrel piece 104 is crushed with the coupling part 103 by caulking at the front part of the wire connection part 102, so that the core W1 of the wire W is surrounded by the barrel piece 104. Therefore, as the position of the tip end of the core W1 cannot be confirmed, positioning precision for the wire W in a crimping process is required. This might cause various troubles. For example, labor and time for the crimping process increases, causing deteriorated efficiency; a connection failure occurs between the core W1, that is shifted backward, and the serration part 105; or the caulking resistance increases due to the core W1 shifted forward.